The noise heard when the system is first turned on is not due to a defect. In the event of persistent noise, check for the presence of one of the following malfunction causes and apply the corresponding solution.

In the following instances, a few defective components of the system create an incorrect inlet and outlet pressure. This phenomenon causes noise in the compressor that is actually due to one of the causes listed below and NOT the compressor itself:

  • • Incorrect amount of refrigerant (30-35% more or 70-75% less)

  • • Expansion valve shut or blocked

  • • Compressor displacement regular valve defective (for variable displacement compressors only)

  • • Clogging in the system circuit

  • • Filter saturated with moisture



belt worn or slipped

check the wear and tension of the belt

belt idler pulley is noisy

replace it

electronic clutch plate slipping

make sure that the distance between the compressor pulley and electric clutch is 0.3-0.5mm

vibration and resonance of the compressor support plate

make sure the bolts are tight and the plate is properly positioned

expansion valve “whistles”

if noise persists, replace the valve

belt diagram 2
belt diagram 1